由分散相互作用指导的金属有机框架中的区域选择性原子层沉积
Leighanne C Gallington1, In Soo Kim2, Wei-Guang Liu3
1X-ray Science Division, Advanced Photon Source, Argonne National Laboratory , Argonne, Illinois 60439-4858, United States.
Journal of the American Chemical Society
|October 5, 2016
概括
原子层沉积 (ALD) 精确地功能化了金属有机框架 (MOF). 研究人员可视化了MOF毛孔中的ALD区域选择性,揭示了由前体吸附和分散相互作用驱动的偏好沉积.
科学领域:
- 材料科学
- 纳米技术
- 化学工程
背景情况:
- 原子层沉积 (ALD) 允许精确的薄膜生长在表面上.
- 金属有机框架 (MOF) 具有复杂的孔隙结构和表面化学.
- 由于其复杂的结构,对MOF的ALD提出了独特的挑战.
研究的目的:
- 研究ALD对MOF用于合成设计功能材料的应用.
- 了解MOF毛孔内的ALD的沉积行为和区域选择性.
- 为了阐明观察到的沉积模式背后的驱动力.
主要方法:
- 在现场同步X射线粉碎衍射以可视化ALD期间的原子定位和再分配.
- 密度功能理论 (DFT) 计算以建模前体吸附和相互作用.
- 通过ALD修改的MOF的合成和特征.
主要成果:
- 在MOF NU-1000中,ALD表现出区域选择性沉积.
- 在较小的毛孔中发生氧- (II) 种的偏好沉积.
- 在偏好的吸附点的分散相互作用驱动区域选择性.
结论:
- ALD可以在MOF中精确控制,提供定制功能材料的途径.
- 在MOF中ALD的区域选择性是由前体-表面相互作用决定的.
- 这项研究为复杂的多孔材料中的ALD过程提供了基本的见解.
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